Mining cutter bit



Nov. 28, 1961 N. BENTLEY ETAL 3,010,709

MINING CUTTER BIT Filed March 17, 1959 26 -I r l4 1.9 R2;

INVENTORS Mfln aap 654 71 5 J0. firm 41 ATI'III RN EYE United States Patent 3,010,709 MINING CUTTER BIT Norwood Bentley, Van, and J. 0. Townley, Danville, W. Va. Filed Mar. 17, 1959, Ser. No. 800,044 6 Claims. (Cl. 262-33) This invention relates to cutter bits used in chain cutters of mining machines and wherein the bits are readily removed and replaced, and in particular a bit having a conventional shank that is received in a holder of a chain and wherein the cutter portion of the bit is provided with a broad extended cutting edge with side surfaces following the cutting edge relieved and tapering inwardly and with the lower supporting portion at the base of the bit bulging outwardly reinforcing the bit and preventing the cutting portion breaking away from the mounting shank.

The purpose of this invention is to expedite the operation of chain cutters of mining machines by providing a bit having a broad cutting edge and by reinforcing the supporting portion of the bit whereby the life of the bit is extended. v

Conventional bits used in chain cutters of mining rnachines are cut from bar stock, diamond-shaped in cross section wherein cutting points extend from both ends, or the bits are formed with semi-circular cutting edges and with parallel sides following the cutting edges resulting in excessive friction resulting from rubbing of the side surfaces on the sides of the cut.

Other bits have been provided in various designs, however, such bits retard the cutting operation and due to the abuse to which such bits are subjected the life of the bit is comparatively limited.

With this thought in mind this invention contemplates a cutter bit of an improved design wherein side surfaces of the cutting portion are relieved providing converging portions in plan and are extended outwardly providing diverging edges in front elevation with the lower portion from which the mounting shank extends enlarged or bulging outwardly reinforcing the base of the bit and providing a bit that cuts efficiently and that wears longer than conventional bits.

The improved cutter bit of this invention is provided with a carbide cutting edge that further extends the life of the bit.

The object of this invention is, therefore, to provide an improved cutter bit for cutter chains wherein the bit is provided with a broad cutting edge and wherein the broad cutting edge is supported by an enlarged base portion from which a mounting shank extends.

Another object of the invention is to provide an improved cutter bit for chain cutters in which the bit is provided with a shank of conventional size so that the bit may be mounted in chains now in use.

Another important object of the invention is to provide an improved cutter bit for cutter chains in which the bit is provided with a mounting shank by which the bit may be installed in conventional chains without changing parts of the chains.

A further object of the invention is to provide an improved cutter bit for chains in which the bit is of a simple and economical construction.

With these and other objects and advantages in view the invention embodies a cutter bit having a broad cutting edge with side surfaces relieved immediately following the cutting edge and reinforced toward the mounting base and at the intersection of the base with a. shank for mounting the bit in a holder of a chain.

Other features and advantages of the invention will appear from the following description taken in connection with the drawing, wherein:

3,010,799 Patented Nov. 28, 1961 FIGURE 1 is a side elevational View illustrating the improved cutter bit.

FIGURE 2 is a front elevational View looking toward the cutting edge of the bit.

FIGURE 3 is a plan view of the cutter bit.

FIGURE 4 is a cross-section through the cutter bit taken on line -44 of FIGURE 1 showing the body integrally connected to the shank of a conventional cutter bit.

FIGURE 5 is a perspective View looking from a slightly different angle to that of FIGURE 1 and also illustrating the formation of the bit.

Referring now to the drawing wherein like reference characters denote corresponding parts the improved cutter bit of this invention includes a broad cutting edge 10, a body 11 at the top of the leading face of which the cutting edge 10 is positioned and a mounting shank 12 which is diamond-shaped in cross section and which is designed to be received in a conventional holder of a chain cutter.

Side surfaces '13 and 14 following the cutting edge 10 of the body 11 are relieved, being inclined inwardly in converging relation to a heel or point 15 whereby as the cutting edges 16 and 17 cut through material the surfaces 13 and 14 are spaced from the sides of the cut eliminating the possibility of friction resulting from a cutting operation where the sides are parallel.

The side surfaces '13 and 14 taper outwardly, as shown in FIGURE 2 to a point '18 on the leading surface of the bit and from the point 18 the surfaces bulge outwardly blending into arcuate bulging surfaces 19 and 20, as shown in FIGURES 2 and 5 thereby reinforcing the base at the intersection of the body 11 of the cutter bit and the mounting shank 12 which, being diamondshaped in cross section, is provided with a fore point 21, side points 22 and 23 and an aft point 24.

The mounting shank 12. is of the same size as shanks of conventional cutters whereby the shank is received in a conventional holder of a chain cutter.

With the cutter bit formed in this manner the cutting edge 10 advances into material, such as coal or ore in a mine with side surfaces of the cutter bit spaced from the Walls of the cut thereby eliminating friction and with the cutting edge reinforced by the backing portion extended from the point 10 to a point 25 and with the lower base portion at the intersection of the body of the bit with the shank reinforced by the outwardly bulging portions 1 5 and 20.

With the parts formed in this manner and with the leading edge formed of car-bide the life of the bit is extended and the possibility of breaking between the cutting edge or body and shank is substantially eliminated.

It will be understood that the cutter bit may be used in cutter chains of different types and designs and cutter chains with the cutter bits installed therein may be used for different purposes.

It will also be understood that the cutter bit may be mounted in cutter chains of this type by other means.

The improved cutter bit of this invention combines ruggedness and speed and can be used on any chain cutter that uses a throw away bit.

The broad cutting edge 10 is provided on a strip 26 of carbide or other similar material which is integrally secured to the body of the bit, as shown. 7

Although the improved cutter bit of this invention is of the throW-a-way type this bit is not discarded after use, but is reground or resharpened and reused continuously.

Conventional chains for holding cutter bits are provided in links and the links support the cutter bits in different radially disposed positions, whereby, although the cutting edge of the bit is only about Mr inch wide the chain cuts an opening about six inches Wide.

It will be understood that modifications, within the scope of the appended claims, may be made in the design and arrangement of the parts without departing from the spirit of the invention.

What is claimed is:

l. A cutter bit comprising a body having an elongated mounting shank extended therefrom said shank being of substantially diamond shaped in elevation and said body having a broad cutting edge on the upper leading face, side surfaces of the body following the cutting edge being relieved and converging and the lower portion of the body bulging outwardly from the relieved side surfaces providing a reinforced section at the intersection of the body and mounting.

2. A cutter bit comprising a body and a mounting shank, said shank being substantially diamond shaped in cross section transversely of the length thereof, the body being enlarged at the intersection thereof with the mounting shank providing a reinforced base portion of the body, the body having a broad cutting edge at the leading upper end with side surfaces following the cutting edge relieved and with the forward surface inclined rearwardly from the cutting edge.

3. A chain cutter bit comprising a body and an elongated shank integral therewith, the shank being substantially diamond-shaped in cross section transversely of the length thereof, the body having a broad cut-ting edge on the leading end with the end surface below the cutting edge inclined rearwardly and with side surfaces thereof relieved following the cutting edge and blended into outwardly bulging portions at the intersection of the body with the shank whereby the lower portion of the bit is reinforced.

4. In a cutter bit, the combination which comprises a substantially rectangular shaped body and a mounting shank integral with said body, with said shank being substantially diamond shaped in cross section transversely of the length thereof, the body having a broad cutting edge on the leading face and being inclined rearwardly from said cutting edge, the side surfaces of the body being relieved and positioned in converging relation from the cutting edge to a heel portion and said side surfaces blending into outwardly bulging portions at the intersection of the body with the shank.

5. In a cutter bit, the combination which comprises a substantially rectangular shaped body and an elongated mounting shank integral therewith, the body having a broad cutting edge on the leading face and being inclined rearwardly from said cutting edge, the side surfaces of the body being relieved and positioned in converging relation from the cutting edge to a heel portion and said side surfaces blending into outwardly bulging portions at the intersection of the body with the shank, and the shank being substantially diamond-shaped in cross section transversely of the length thereof, elongated and of a size suitable for mounting a holder of a conventional chain cutter.

6. In a cutter bit as in claim 5 wherein said cutting edge is formed from a strip of carbide steel that is rigidly secured to said body on the leading surface thereof.

References Cited in the file of this patent UNITED STATES PATENTS 2,227,737 Osgood Jan. 7, 1941 2,575,980 Simmons Nov. 20, 1951 2,645,471 King July 14, 1953 2,907,559 Brown et al. Got. 6, 1959 2,933,295 Rollins Apr. 19, 1960 

